To estimate the prevalence of DMD and characterize commercially- and Medicaid-insured registrants with DMD in the US. 

DMD is a severe X-linked neurodegenerative disease, associated with early mortality. Previous studies have estimated the prevalence and natural history of DMD, however, the characteristics of patients with Medicaid vs. commercial coverage in the US is unknown.

MarketScan Commercial and 10-State (anonymized) Medicaid claims from 2013 to 2018 were used to identify males ≤30 years old with DMD (ICD: 359.1, G71.0). The median age and prevalence of neurologic/neuropsychiatric comorbidities at baseline were summarized. Counts were estimated over the period and DMD prevalence in the last year of the period; the distribution of cases by age was tabulated. Attrition at 3- and 5-years was estimated using Kaplan-Meier analysis.

The median age at baseline was similar between the commercial (15 years; n=1,834) and Medicaid (14 years; n=1,880) cohorts. Neurological/neuropsychiatric comorbidities were observed in 23.6% of commercially-insured and 40.9% of Medicaid-insured DMD patients. DMD prevalence per 100,000 males <30 years of age was higher in the Medicaid (35.7) vs. the commercial (16.2) cohort. Among commercially-insured DMD patients, 28.8% were <10 years, 42.2% were 10 to <20 years, and 28.9% were 20 to ≤30 years, of age in the last year of the period; corresponding values from the Medicaid cohort were 20.4%, 48.1%, and 31.5%. Fewer commercially-insured DMD patients remained in the cohort at 3 (56.4%) and 5 (39.0%) years compared to Medicaid-insured patients (79.4% [3 years] vs. 46.1% [5 years]).

Despite similarities in median age, the age distribution suggests registrants with DMD in Medicaid are slightly older than in commercial plans. Insurance coverage attrition among Medicaid registrants with DMD was lower than among commercially-insured individuals.